C++ 中 <iterator> <functional> <numeric> 库好用的函数详解

function advance(&it, n):
	while n > 0:
		--n
		++it
	while n < 0:
		++n
		--it

function advance(&it, n):
	it += n

function next(it, n = 1): -> iterator
	std::advance(it, n)
	return it
function prev(it, n = 1): -> iterator
	std::advance(it, -n)
	return it

function distance(first, last):
	result := 0
	while first <> last:
		++first
		++result
	return result

function distance(first, last):
	return last - first

function iota(first, last, value):
	while first <> last:
		[first] := value
		++first
		++value

function accumulate(first, last, init): -> type
	while first <> last:
		init := init + [first]
		++first
	return init

function accumulate(first, last, init, op): -> type
	while first <> last:
		init := op(init, [first])
		++first
	return init

function partial_sum(first, last, d_first): -> iterator
	if first == last:
		return d_first
	[d_first] := [first]
	sum := [first]
	while ++first <> last:
		sum := sum + [first]
		[++d_first] := sum
	return ++d_first

function partial_sum(first, last, d_first, op): -> iterator
	if first == last:
		return d_first
	sum := [first]
	[d_first] := sum
	while ++first <> last:
		sum := op(sum, [first])
		[++d_first] := sum
	return ++d_first

function adjacent_difference(first, last, d_first): -> iterator
	if first == last:
		return d_first
	acc := [first]
	[d_first] := acc
	while ++first <> last:
		val := [first]
		[++d_first] := val - acc
		acc := val
	return ++d_first

function adjacent_difference(first, last, d_first): -> iterator
	if first == last:
		return d_first
	acc := [first]
	[d_first] := acc
	while ++first <> last:
		val := [first]
		[++d_first] := op(val, acc)
		acc := val
	return ++d_first